Flame-arc lamp and electrode therefor.



G. EGLY. D ELECTRODE THER FLAME ARC LAMP n APPLIcATf N FILED snr'r. 9,

BFOR.

Patented Ma r. 16, 1915 ADM/XTURFS Ll/VES GEORG EGLY, OF BERLIN-TREITOW, GERM 00., OF BERLIN-LICHTENBERG, GERM ANY, ASSIGNOB. TO- GEBR'U'DER SIEMENS & ANY, A CORPORATION OF GERMANY.

FLAME-ABC LAMP AND ELECTRODE THEREFOR.

Specification of Letters Patent.

Patented Mar. 16, 1915.

Application filed September 9, 1914. Serial No. 860,874.

To all whom it may concern:

Be it known that I, Gnoae EGLY, a Ger man citizen, and resident of Berlin-Troptow, Germany, have invented certain new and useful Improvements in Flame-Arc Lam s and Electrodes 'lherefor, of which the 'ollowing is a specification.

In arc lamp electrodes having mineral admixtures especially in case one electrode is mounted above the other frequently a formation of slag will take place atthe negative electrode which will prevent the lamp from properly operating. This formation of slag at the negative electrode is due to the fact that particles of luminou salts of the positive electrode are carried by the arc 'towardthe negative electrode, which particles by reason of the low temperature of the negative electrode will not be caused to'evaporate but only undergo melting and deposit in the form of pearls thus being a cause forv the non-ignition of the lamp. With decreasing current strength this formation of slag will come more into effect and the ordinarily employed auxiliaries for preventing the formation of slag at the electrode by admixtures of salts of the alkaline metals will not be effective.

In order to prevent the formation of slag at the negative electrode a pure or ordinary cored carbon has been employed. By this, however, the slag formation and the consequent troubles could not be avoided. According to my present invention I entirely obviate this disadvantage by embodying exclusively salts of the alkalis into the negative electrode and in even distribution throughout themass thereof. For this purpose for instance the carbonates, borates, and so forth, may be used, that is to say potash, sodium carbonate, borax, and so forth. The alkaline salts in the electrode have the purpose to again cause-the evaporation of the luminous materials which arrive from the positive electrode and deposit upon the negative electrode, before these a materials unite themselves to form moltenpearls.-

-I have incorporated my present invention in the accompanying drawing, in which a designates the upper or positive, b the lower or negative electrode, and in which the composition of these electrodes, as above pointed out, is indicated by proper legends.

Having thus described my invention I .claim as new and desire to secure by Letters Patent of the United States 1. A flame arc lam com rising in combination a negative eectro e comprising as an essential ingredient a slag removing admixture in the form of alkaline salts such as carbonates, boratesor the like, evenly distributed throughout the mass of said electrode, and a positive electrode containing luminous admixtures.

2. A flame arc lamp comprising in combination a negative electrodecontaining as an essential ingredient a slag removing admixture in the form of borates evenly dis tributed throughout the mass of said elec-v trode and a positive electrode comprising luminous admixtures.

In testimony whereof- I have hereunto set my signature in the presence of two sub scribing witnesses.

(arEORGr EGLY.

\Vitnesses HENRY HASPER, WOLDEMAR HAUPT. 

